Add support for button entities (#2824)

esphome/components/mqtt/__init__.py

@@ -95,6 +95,7 @@ MQTTSwitchComponent = mqtt_ns.class_("MQTTSwitchComponent", MQTTComponent)
 MQTTTextSensor = mqtt_ns.class_("MQTTTextSensor", MQTTComponent)
 MQTTNumberComponent = mqtt_ns.class_("MQTTNumberComponent", MQTTComponent)
 MQTTSelectComponent = mqtt_ns.class_("MQTTSelectComponent", MQTTComponent)
+MQTTButtonComponent = mqtt_ns.class_("MQTTButtonComponent", MQTTComponent)
 
 MQTTDiscoveryUniqueIdGenerator = mqtt_ns.enum("MQTTDiscoveryUniqueIdGenerator")
 MQTT_DISCOVERY_UNIQUE_ID_GENERATOR_OPTIONS = {

esphome/components/mqtt/mqtt_button.cpp

@@ -0,0 +1,40 @@
+#include "mqtt_button.h"
+#include "esphome/core/log.h"
+
+#include "mqtt_const.h"
+
+#ifdef USE_MQTT
+#ifdef USE_BUTTON
+
+namespace esphome {
+namespace mqtt {
+
+static const char *const TAG = "mqtt.button";
+
+using namespace esphome::button;
+
+MQTTButtonComponent::MQTTButtonComponent(button::Button *button) : MQTTComponent(), button_(button) {}
+
+void MQTTButtonComponent::setup() {
+  this->subscribe(this->get_command_topic_(), [this](const std::string &topic, const std::string &payload) {
+    if (payload == "press") {
+      this->button_->press();
+    } else {
+      ESP_LOGW(TAG, "'%s': Received unknown status payload: %s", this->friendly_name().c_str(), payload.c_str());
+      this->status_momentary_warning("state", 5000);
+    }
+  });
+}
+void MQTTButtonComponent::dump_config() {
+  ESP_LOGCONFIG(TAG, "MQTT Button '%s': ", this->button_->get_name().c_str());
+  LOG_MQTT_COMPONENT(true, true);
+}
+
+std::string MQTTButtonComponent::component_type() const { return "button"; }
+const EntityBase *MQTTButtonComponent::get_entity() const { return this->button_; }
+
+}  // namespace mqtt
+}  // namespace esphome
+
+#endif
+#endif  // USE_MQTT

esphome/components/mqtt/mqtt_button.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+
+#ifdef USE_MQTT
+#ifdef USE_BUTTON
+
+#include "esphome/components/button/button.h"
+#include "mqtt_component.h"
+
+namespace esphome {
+namespace mqtt {
+
+class MQTTButtonComponent : public mqtt::MQTTComponent {
+ public:
+  explicit MQTTButtonComponent(button::Button *button);
+
+  // ========== INTERNAL METHODS ==========
+  // (In most use cases you won't need these)
+  void setup() override;
+  void dump_config() override;
+
+  /// Buttons do not send a state so just return true.
+  bool send_initial_state() override { return true; }
+
+  void send_discovery(JsonObject &root, mqtt::SendDiscoveryConfig &config) override {}
+
+ protected:
+  /// "button" component type.
+  std::string component_type() const override;
+  const EntityBase *get_entity() const override;
+
+  button::Button *button_;
+};
+
+}  // namespace mqtt
+}  // namespace esphome
+
+#endif
+#endif  // USE_MQTT